In my post about CZs, I mentioned moissanite, and it deserves its own moment in the diamond-simulant sun.
Moissanite, a mineral, is nearly as hard as diamond (9.25 on the Mohs hardness scale, compared to diamond's 10). Its durability, compared to CZ, is one of the few real benefits of the material. Lab-grown by Charles & Colvard (C&C), who hold the US and international patents, it has been promoted as a stone in its own right, rather than simply a diamond substitute. When it was first marketed, there was a kerfuffle abut jewelers being fooled. This is no longer the case.
Does it look like diamond?
Yes, in smaller sizes, up to around 75 points (three-quarters of a carat). As the stone gets larger, moissanite's darkness (like a J-K diamond) and its particular light-dispersal qualities (known as "doubly-refractive") become evident, and in sizes about 1 ct. it looks hazy, yellowish or grayish. It's hard to generalize, because diamond cuts vary so widely, but a moissanite 's fire (known to gemologists as dispersion) looks 'chunkier', producing too much flash of colour, compared to the arpeggio play of beautifully-cut diamond.
Though I have seen several attractive pieces, I'm not drawn to their concurrent flashiness and flatness.
Is it worth the price?
At around $500 per carat, moissanite is marketed as a desirable stone in its own right, but I'm not sold. Because the producer sells to retailers, you are unfortunately stuck with how they set it, though you can buy loose moissanite. Therefore, nearly all set stones I've seen have a generic look.
Here's an exception, a mokume-gane engagement and wedding ring set (shown with the man's band, above) from Diamond Peak Goldsmiths, of Fort Collins, Colorado, that shows what can be done by skilled designers.
Moissanite from C&C can be recut. One online jeweler says (on a discussion board, www.simstalk.com), "Because C&C cut their stones to maximize profit, they are shallow in crown and depth."
Good CZ looks better because it's whiter, and well-cut white sapphire (starting around $300 per carat) is striking, but not as lively. GGG (Gadolinium Gallium Garnet), is also praised by gemologists for it's diamond-like look, but too soft (6.5 on the Mohs scale) to wear in a ring.
Buy worry-free CZs for far less, enjoy the ease, and spend the difference elsewhere, or save for a conflict-free Canadian diamond. Retail diamond prices are forecast to decline by about 15% this year, but I predict more significant bargains in the vintage market.